1. Field of the Invention
The present invention relates to a camera module, particularly to a camera module configured to adjust a lens focus in a camera module having a selective focus adjusting function, and a method thereof
2. Description of the Related Art
Camera modules are mounted on a portable terminal having various camera functions such as portable telephones and PDAs (Personal Digital Assistants). The camera module receives a desired image through a photographing device, displays the input image on an image display device for presentation, stores the image as an image file by a photographing selection of a photographer, and outputs the stored image file.
Such a camera module is provided with an auto focus (AF) function for being to the point to a to-be-photographed subject for gaining a good pictorial image.
Ordinarily, as a condition of successfully performing an autofocus function, a high contrast, a high S/N ratio (hereinafter, signal to noise ratio), etc. are pointed out. In a case a contrast is humble or an S/N ratio is low, an auto focus may not be carried out properly in low brightness. Therefore, in order to enhance reliability of an auto focus in low brightness, a methodology of increasing a contrast using an IR signal (infrared signal) or maintaining an S/N ratio by keeping film speed pursuant to ISO (International Standards Organization) is employed. For a portrait focused photograph, an AF processing of recognizing the face of a subject by a picture image recognition processing and executing an auto focus to be to the point to the recognized corresponding face position recently emerges also. However, an auto focus region setting in a camera module is extremely limited unlike a DSLR (Digital Single Lens Reflex) having an auto focus region selectable by a user.